Atrai river during monsoon, a view from Atrai Upazila, Naogaon District, Bangladesh

The Atrai was formerly one of the greatest rivers of north Bengal for it was the main channel by which the waters of the Teesta discharged into the Ganges. In 1787, however, the Teesta broke away from its ancient bed and cut for itself a new and capacious channel by which it found its way into the Brahmaputra. Since then the Atrai has lost its importance and has now few traces of its former greatness.

It enters the district[clarification needed] from Rajshahi flowing through the Chalan Beel and falls into the Baral near the village of Nurnagar. Formerly, it used to pursue a course to the south and east after leaving the Chalan Beel till it fell into the Jamuna; but the middle portion of this old channel has been obliterated by the Baral and the Ichhamati, which, taking off from the Padma cut across the Atrai and overwhelmed it by copious deposit of silt.

The southern portion of the river in this district can still be traced from its junction with the Ichhamati at Boalmari; it then flows through Dulai and Bera thana and falls into the Padma near Ratanganj. This river presents one of the most striking instances of riverine changes in the district of Pabna.